User blog comment:Yoshi574930Cool/WHAT IS HIGH BEAUTY/@comment-32358261-20180204011203

In gen 3, gen 4 (not hgss) and gen 6 (not xy), there was a mini game called contests. In these games you had to rank up by making your Pokémon more beautiful, cool, cute etc by feeding them pokeblock or poffins which were made using berries.

From gen 4 and onward the prisim scale was added so you could evolve feebas into milotic without beauty points.

Since PBB lacks contests, the only way to evolve is trading with a prisim scale